基于业务类型的微波与激光混合链路中继卫星接入控制

针对用户星数据中继接入请求超额定购问题,分析了用户星业务种类,研究了中继卫星接入控制所受多类约束的特点,建立了约束满足模型;以接入业务总优先级权值最高为原则,根据业务的类型、时间有效性和业务优先级设置链路接入灵活度和业务冲突集,以业务的接入顺序和选择接入的中继星链路为优化对象,提出了一种基于业务类型和自适应小窗口蚁群算法双层优化的中继卫星混合链路接入控制算法。仿真实验表明,所建模型可实现多类型业务与多种类天线的接入控制,提出的双层优化算法较单层寻优效果更佳,且具有较快的收敛速度和较强的全局优化能力,因而所提算法可有效解决多约束条件下多业务类型、多种类天线和多中继星的接入控制问题。     

星上微波信号光学调制偏置点优化理论及仿真研究

研究了基于双电极马赫曾德尔干涉仪(DE-MZM)的星上微波信号光学调制方法,获得了单频段微波信号输入时的调制器输出光场表达式,推导了载噪比、射频增益、噪声系数及无杂散动态范围四个参数的解析表达式,建立了星上微波光子链路传输方程。利用OptiSystem仿真软件,搭建了单频段微波信号输入时的星上微波光子链路仿真系统,对链路性能进行了仿真研究。研究结果表明,调制器直流偏置点在正交点时,射频信号增益最高;直流偏置点在低偏置点时,载噪比、噪声系数和无杂散动态范围三个性能指标最优。     

磁悬浮分子泵用Hartley涡流传感器

工业领域的磁悬浮分子泵用位移传感器除了要具有良好的静态特性外,还应具有高动态响应特性,同时其体积大小还影响着磁悬浮分子泵的抽速、真空度和压缩比。针对高真空磁悬浮分子泵,提出了一种基于Hartley原理的电涡流位移传感器设计方法,将传感器对称探头接入同一振荡电路作为工作电感。对传感器的动态特性进行了分析,并提出了对其动态响应特性在不影响灵敏度和线性度等静态性能的情况下进行补偿的方法。实验结果表明,在-0.4~0.4mm内,传感器的线性度为±1.17%,灵敏度为9.901mV/μm,分辨率为0.25%,动态响应带宽达到了10.2kHz,两径向四路位移信号测量集成电路板体积仅为π×4~2 cm~2,大大减小了传感器体积,满足了磁悬浮分子泵面向更高抽速和更高真空度的发展需求。     

Isochronal recovery and damage rate measurements in electron-irradiated dilute NiGe

Dilute NiGe alloys were irradiated with 3 MeV electrons below 5 K and subsequently isochronally annealed. In stage II a main recovery stage occurs at 115 K and a smaller one at 150 K both caused by the addition of Ge atoms. Reciprocal damage rates at temperatures immediately above stage I show that single Ge atoms act as stable traps for migrating Ni-selfinterstitials at 73 K. With increasing temperature the trapping radii evaluated from reciprocal damage rates decrease and at temperatures above 115 K trapping of selfinterstitials by Ge atoms cannot be detected any more. The behaviour of the isochronal recovery and of the trapping radii allow us to characterize the 115 K peak as a detrapping stage of interstitials from Ge atoms. Reciprocal damage rates at 73 K performed after pre-irradiations with 3 MeV electrons at high temperatures do not give any indication of a radiation induced segregation of the Ge atoms.     

基于改进多元宇宙算法的主动配电网故障定位方法研究

针对现有智能优化算法在求解主动配电网故障定位问题时存在的收敛速度慢、易陷入局部最优解、容错性差、种群质量低等问题,提出一种改进的多元宇宙优化算法(improved multi-verses optimization, IMVO)。首先构建具有容错能力的主动配电网模型,根据故障定位问题的特点对多元宇宙的种群进行离散化编码。其次将自适应精英策略融入改进算法的多元宇宙种群的更迭中,以保证多元宇宙的种群质量。设计基于非线性曲线变化的虫洞存在概率(wormhole existence probability, WEP)与旅行距离率(travel distance rate, TDR)的更新机制,以提高算法前段搜寻相对最优宇宙的能力与后段调整最优探测距离的精度。最后通过自适应突变操作增强改进算法的局部搜索能力,进而提高全局寻优能力。仿真实验结果表明,改进多元宇宙优化算法在单点、多点以及信息畸变故障定位中全局寻优能力显著,相较于其他优化算法在解决配电网故障定位问题上具有更高的准确率与收敛速率。     

面向多无人车的目标点分配和协同路径规划算法

针对多智能体路径搜索算法在非指定式多车协同路径规划问题中路径冗长,计算效率低等缺陷,提出协同目标点分配 路径规划算法 Nutcracker-CBS。 首先构建紧耦合目标点分配 MAPF 框架,实现目标点分配和路径构建的联合寻优;针对目标点 分配模块,提出改进的星鸦优化算法,增量式求解分配问题,缩短模块用时;针对路径构建模块,提出改进的 MAPF 算法,通过回 退式约束构建机制,引入避碰路径估计的绕道机制和数据共享底层路径规划机制,提升效率和路径质量。 数据集实验中, Nutcracker-CBS 时耗相比 SOTA 算法减少 90. 37% ;目标点分配模块求解耗时减少 86. 76% ;MAPF 模块 6 s 内构建 100 辆无人车 路径,平均路径长度缩短 6. 058% 。 实际实验中路径总和与系统运行时长分别减少 55. 26% 和 61. 29% ,提升了多机器人系统的 效率,降低了路径长度。     

基于AIFCS工业配电系统开关柜设计

在分层分布式控制的基础上,充分利用触摸屏电脑和基于人工智能AI(Artificial Intelligence)系列仪表的现场总线技术AIFCS(Artificial Intelligence Fieldbus Control System)的优点,重点进行了智能开关柜的整体设计、各功能单元设计、保护功能设计、抗干扰设计和监控软件设计等方法研究。样机实现了在模拟工业配电环境中通过RS-485接口控制三相电机、风扇等常用电器设备。智能开关柜能满足工业控制系统分散化、网络化、智能化的要求。     

On the usefulness of epitaxy experiments in evaluating interface models

New results on low energy interfaces for the system gold on sodium chloride are presented together with a short review of the various versions of the sphere-plate technique which are used to study interface systems. The observed low energy orientation relationships as well as those recently found for the systems silver on sodium chloride and silver on silicon are compared with preferred orientations observed in epitaxy experiments. It is concluded that results for epitaxy are extremely useful when evaluating interface models for their predictive power.     

Cd-substituted Mg composites with dual-equivalent permeability and permittivity for high-frequency miniaturization antennas

Spinel Mg ferrites Mg_1-xCd_xCo_0.05Fe_1.95O₄ (x=0.0, 0.2, 0.3 and 0.4) as potential agents for the miniaturization of high frequency antennas are presented. All the synthesized compositions were experimentally revealed to possess pure spinel phase. Dual-equivalent permeability and permittivity (μ'≈26, ε'≈25, x=0.3 and μ'≈29, ε'≈28, x=0.4) from 5 to 100 MHz can be achieved by introducing Cd²⁺ ions, yielding large miniaturization factors of up to 25 and 28. To figure out the effects of Cd²⁺ ions substitution on magnetic and dielectric properties, the change in microstructure is mainly investigated. Meanwhile, enhanced magnetic properties including upward saturation magnetization (Ms) (approximately 47.60 emu/g) and reduced coercivity (approximately 54.22 Oe) are obtained due to increased grain size and denser microstructure arrangements reflected from scanning electron microscopy images. With low magnitude order of magnetic and dielectric losses factors (tanδ_ε reaches 10^-4, tanδ_μ reaches 10^-2), the composites can potentially exhibit high operating efficiencies at high frequencies.